Lightweight construction through structural foam injection molding – Established process for new generation of printers
The current trend for electrical housings – to produce lighter components more energy-efficiently and at lower costs – remains unbroken. In combination with specially developed materials, the structural foam injection molding process is an excellent way to meet these requirements.
Weidmüller uses a rather atypical component to illustrate how to exploit the advantages of the structural foam injection molding process, which go beyond simple weight reduction. The company uses an established process and materials to manufacture the latest generation of its PrintJet ADVANCED of high-performance, high-quality industrial printers.
Makrolon® SF800 Z MAS148, a glass fiber-reinforced polycarbonate developed specially for structural foam injection molding, provides the foundation for meeting the demanding standards for fabrication and component geometry. Amorphous thermoplastics such as filled polycarbonate materials have substantially better dimensional accuracy than glass fiber-reinforced polyamides, for example. This enables the fixing elements of the housing to be positioned very accurately and allows very precise printing even at high speeds because of significantly reduced housing vibrations. The elimination of additional stabilizing structural elements made it possible to produce a simple, cost-effective component. Structural foam injection molding significantly reduce or even eliminate sink marks and shrinkage.
Furthermore, Makrolon® SF800 Z MAS148 exhibits outstanding flame-retardant properties in the foamed state. In contrast to glass fiber-reinforced materials such as polystyrene, polypropylene or ABS, Makrolon® SF800 Z MAS148 can withstand the high temperatures (> 120 °C) inside the printer.
But the structural foam injection molding process also has positive effects with respect to process and plant technology. The improved flowability associated with the process enables the use of a lower closing force, which in turn reduces the amount of energy required.
The main properties of Makrolon® SF800 Z MAS148 polycarbonate grades are:
Particularly well suited for large and thick-walled components; in combination with a suitable blowing agent also for the production of structural foam injection moldings
- High dimensional accuracy
- Medium viscosity
- Easy release agent
- Excellent flame-retardant properties
- Very good coating adhesion